Tonight's the night. Millions of people in the Earth's western hemisphere will be treated to a spectacular event tonight when the moon falls beneath the shadow of the Earth.
The event, called a full lunar eclipse, will cast the moon in an eerie orange light and produce an event colloquially known as a "blood moon." The eclipse will begin at around 2 am and will continue for three hours as the moon becomes dark and eventually passes through the Earth's shadow.
Though not as rare as a solar eclipse, a full lunar eclipse is rare enough that it sparks curiosity among those not familiar with such an event. Like many other celestial happenings, it also brings its share of pseudo-scientific and metaphysical prophecies from astrologers and others. Luckily, real scientists are very familiar with lunar eclipses, their cause, and what people can learn from the events.
Today NASA 's Goddard Space Flight Center released a new video detailing everything most anyone might want to know about the upcoming eclipse. As NASA astronomer Michelle Thaller explains in the video, the sunlight that normally produces the bright reflection seen coming from the moon will be blocked tonight by the Earth itself. Thaller even reveals that the blood moon effect and color is produced because the light reaching the moon passes through the Earth's atmosphere, the same atmosphere that generally reflects more blue light, leaving the red-tinged edge of the visible spectrum to pass through.
As Thaller mentions in the video, NASA's Lunar Reconnaissance Orbiter will be reliant on battery power during the eclipse (it normally runs on solar power). Though this particular eclipse will mean the LRO will have to make two full passes withing the Earth's shadow during the event, NASA's LRO project scientists will be shutting off many of the probe's instruments and are confident that the LRO will survive this eclipse, as it has many others.
Image via NASA